At one time, poplar trees must have grown on Poplar Island.

VOA: special.2009.10.06

A famous mathematician once said "Every question must have a correct answer " for every question one answer."

一位著名的数学家曾说过,“每一个问题都必定有一个正确的答案,每一个人们所回答的问题“

耶鲁公开课 - 政治哲学导论课程节选

And one thing that Einstein put forth is he figured if well, what we're saying is that light is, in fact, a stream of particles, each one of those particles or photons must, therefore, have a momentum.

爱因斯坦提出了一件事情,他指出如果我们所说的光，事实上是一束粒子，那么这些粒子或者光子中的，每一个都有动量。

麻省理工公开课 - 化学原理课程节选

Each piece must have at least one good "eye,"

VOA: special.2009.03.10

One is people must have had an incredible amount of confidence in Jonas Salk.

乔那斯?索尔克这个人,有着强大的自信

耶鲁公开课 - 生物医学工程探索课程节选

But since, number one, I wasn 't hungry but thirsty, and number two, they was free, I must have drank meabout 15 Dr. Peppers.

VOA: standard.other

One question is this: Is it really true that in order to think about the perfectly straight, I must have somehow, somewhere at some point come up against, had direct knowledge of, the perfectly straight?

一个问题是,难道真的说,为了想象一条完美的直线,我必须,在某处直接碰到,并直接了解一条完美的直线吗

耶鲁公开课 - 死亡课程节选

And when Hobbes tells that story, which he mentions a couple of times in the book, one can only imagine he must have had a kind of wry grin on his face when he wrote that out.

霍布斯在书中几次提到，当借用这个故事的时候，你能想象到,他的脸上呈现的会是怎样的苦笑。

耶鲁公开课 - 政治哲学导论课程节选

If you're not taking notes in this lecture, you have to write down at least one sentence. You must write this down because this will be the most important thing I say all morning: Milton's Paradise Lost is the first narrative poem in English that didn't rhyme.

就算你们这堂课不记笔记，也一定要记下至少一句话，一定要把这记下来,这是我一早上说的最重要的一句话了：,弥尔顿的《失乐园》是,第一首不押韵的英语叙事诗。

耶鲁公开课 - 弥尔顿课程节选